Ballmer pushes any rising star within Microsoft out before they have the chance to potentially replace him

An ex-Microsoft executive, who will release a new book about his experiences with the company, said that current CEO Steve Ballmer is anything but fit for the role.

Joachim Kempin, a former Microsoft employee from 1983-2002, recently wrote a book called "Resolve and Fortitude: Microsoft's 'Secret Power Broker' Breaks his Silence" that will be published today.

The book details Ballmer's role as CEO, and how he has kept that position for so long. According to Kempin, Ballmer pushes any rising star within Microsoft out before they have the chance to potentially replace him.

Kempin first witnessed this when it happened to Richard Belluzzo, a former Hewlett-Packard executive that launched the Xbox console. He eventually made his way up to chief operating officer, but after only 14 months as COO, Belluzzo left.

"He (Belluzzo) had no room to breathe on the top," said Kempin. "When you work that directly with Ballmer and Ballmer believes 'maybe this guy could someday take over from me', my God, you will have less air to breathe, that's what it comes down to."

Kempin said this also happened with other major Microsoft executives, including Kevin Johnson, a former Windows head that left to run Juniper Networks Inc.; Stephen Elop, a former Office chief that went to Nokia; Ray Ozzie, a software extraordinaire that left to start his own project, and Steven Sinofsky, former Windows chief that left right after Windows 8 launched.

Sinofsky, former president of Microsoft's Windows and Windows Live division, announced that he was leaving the company last November after 23 years with the company. While Sinofsky was seen as a brilliant figure at Microsoft, his downfall was that he didn't get along with others within the company. He was notorious for picking fights with other executives, including Ballmer.

So why exactly does Ballmer feel threatened? According to Kempin, it's because Ballmer isn't fit for the CEO role, and that Microsoft could use a new fresh face at the helm.

"Is he a great CEO? I don't think so," said Kempin. "Microsoft's board is a lame duck board, has been forever. They hire people to help them administer the company, but not to lead the company. That's the problem. They need somebody maybe 35-40 years old, a younger person who understands the Facebook Inc generation and this mobile community. They don't need this guy on stage with this fierce, aggressive look, announcing the next version of Windows and thinking he can score with that."